http://code.google.com/p/proxmark3/wiki/Compiling

sudo apt-get install build-essential libreadline5 libreadline-dev libusb-0.1-4 libusb-dev libqt4-dev perl pkg-config

dpavlin@t61p:/tank/proxmark3$ svn co http://proxmark3.googlecode.com/svn/trunk proxmark3

dpavlin@t61p:/tank/proxmark3$ sudo ./proxmark3/tools/install-gnuarm4.sh /tank/proxmark3/gnuarm/ /tank/proxmark3/tmp/